1. Field of the Invention
The present invention relates generally to a differential assembly and, more particularly, to a selectively lockable differential assembly for use in the drivetrain of a motor vehicle.
2. Related Art
Limited slip differentials are commonly used in the automotive industry for the purpose of enhanced vehicle mobility, by diverting torque to the wheel with the greatest traction, during periods when one wheel slips due to contact with a low coefficient surface. Limited slip differentials typically include one or more clutch packs which may be passively preloaded as a result of the differential gear separation forces which vary with applied torque to the differential or may be selectively locked, so as to limit or prevent differential rotation between the two output shafts of the differential. Prior lockable differentials have included those incorporating parallel-axis differential gears, such as spur or helical gears, and a magnetic or hydraulic power source for activating the clutch pack. The spur and helical gears used in such differentials, may lack sufficient impact strength for particular applications.
Another known lockable differential utilizes bevel gears which are inherently stronger than the aforementioned parallel-axis gears. In this known system, the differential clutch pack is hydraulically activated.
At the time of the present invention, automotive design engineers continue to search for new and improved selectively lockable differentials.